1. Field of the Invention
The present invention relates to a fastener, more particularly to a fastener for securing a container on the deck of a cargo vessel or ship in which the fastening tension can be easily and simply adjusted and ineffective fastening can be avoided.
2. Description of the Related Art
Generally, when containers are being transported in a cargo vessel or ship, in order to prevent undesired movement or toppling down of the containers 11 stacked on the ship as shown in FIG. 1, lashing ropes 2 and fastening assemblies 3 are used to secure the containers 11 to deck fittings (not shown) on a deck 12 of the ship. The conventional fastening assembly 3 includes a connecting member 31 and a connecting rod 32 that are connected in threaded engagement. However, when the ship pitches and rolls in a stormy sea, the threaded connection may be loosened thus resulting in disengagement of the connecting member 31 from the connecting rod 32 and, hence, ineffective fastening.
U.S. Pat. No. 6,666,634 proposes a “Positioning Assembly for Positioning a Container on a Platform,” which was intended to overcome the aforesaid drawback of the conventional fastening assembly. The positioning assembly includes a limiting seat formed with a limiting hole, and a platform-connecting rod that engages threadedly a container-connecting unit and that has an engaging stud portion for engaging the limiting hole to arrest rotation of the platform-connecting rod, thereby preventing undesired disengagement of the platform rod from the container-connecting unit. However, the limiting seat may still disengage from the platform-connecting rod due to severe rocking of the ship.
In pending U.S. patent application under Ser. No. 10/868,288 entitled, “Fastener for Securing a Container on a Vehicle,” a first fastener component of a fastener assembly disclosed therein includes a lock body mounted slidably on two rails which bridge a pair of fixed bodies. A threaded stem of a second fastener component extends between the two rails as it is passed threadedly through a screw hole formed in one of the fixed bodies. In use, the stem is not rotatable when connected to a deck fitting. The first fastener component is connected to a rope and is turnable relative to the stem to tension or loosen the rope. The lock body, when engaging a locking portion on the stem, restraints relative rotation between the stem and the first fastener component so that the rope is prevented from becoming loosened undesirably.
While such fastener structure is quite satisfactory in providing reliable engagement and preventing slippage of the lock body from the stem, it is noted that upon assembly and connection of such a fastener to a deck fitting on the ship, the fastening tension can only be adjusted by first releasing the lock body from the stem, rotating the first fastener component with the lock body relative to the stem until the desired tension is obtained, and then placing the lock body back onto the stem. Such process of operation is somewhat complicated.
The present invention intends to overcome such a shortcoming while still providing a reliable engagement between the lock body and the stem of the second fastener component and preventing undesirable loosening of the rope caused by inadvertent relative rotation between the stem and the first fastener component in use.